All current intelligent electronic devices (such as smartwatches and smart bands) start to support real-time heart rate detection. In this case, a user carrying an intelligent electronic device can detect a heart rate change in real time during daily life or exercise to take exercise scientifically. However, a photoplethysmography (PPG) sensor is a device that consumes a significant amount of power. Keeping the sensor normally on greatly affects standby time of the device, affecting user experience of an intelligent electronic device. To resolve this problem a timing detection manner is used during real-time detection, for example, heart rate detection is started once every 10 minutes, that is, detection is started at regular intervals repeatedly, and a sampling rate of the sensor is fixed at a constant sampling rate.
The manner of starting a detector at regular intervals to detect a heart rate and performing sampling using a constant sampling rate cannot be used to accurately detect a heart rate condition of a user.